:root {
    font-family: Arial, sans-serif;
    color: #111827;
    background: #f7f7f8;
}

body {
    margin: 0;
}

.page-shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px;
}

.card {
    width: 100%;
    max-width: 900px;
    background: white;
    padding: 28px;
    border-radius: 16px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.08);
}

h1 {
    margin: 0 0 8px;
}

.muted {
    margin-top: 0;
    color: #6b7280;
}

.form {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
    margin-top: 24px;
}

.field {
    display: grid;
    gap: 6px;
}

label {
    font-size: 14px;
    font-weight: 600;
}

input {
    box-sizing: border-box;
    width: 100%;
    padding: 12px;
    border: 1px solid #d1d5db;
    border-radius: 10px;
    font-size: 15px;
}

select {
    box-sizing: border-box;
    width: 100%;
    padding: 12px;
    border: 1px solid #d1d5db;
    border-radius: 10px;
    background: white;
    font-size: 15px;
}

input:read-only {
    background: #f3f4f6;
}

input:invalid,
select:invalid {
    border-color: #dc2626;
}

.split-inputs {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.form-message {
    grid-column: 1 / -1;
    min-height: 20px;
    color: #991b1b;
    font-size: 14px;
}

button {
    grid-column: 1 / -1;
    margin-top: 8px;
    padding: 12px;
    border: none;
    border-radius: 10px;
    background: #111827;
    color: white;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
}

button:hover {
    background: #030712;
}

@media (max-width: 640px) {
    .form {
        grid-template-columns: 1fr;
    }
}

.alert {
    margin-top: 16px;
    padding: 12px;
    border-radius: 10px;
    font-size: 14px;
}

.alert-error {
    background: #fee2e2;
    color: #991b1b;
}

.alert-success {
    background: #dcfce7;
    color: #166534;
}

.viewer-shell {
    min-height: 100vh;
    background: #fff;
}

.viewer-frame {
    position: relative;
    min-height: 100vh;
}

.viewer-iframe {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: 0;
}